package com.itheima.reggie.filter;

import com.alibaba.fastjson.JSON;
import com.itheima.reggie.common.BaseContext;
import com.itheima.reggie.common.R;
import jakarta.servlet.*;
import jakarta.servlet.annotation.WebFilter;
import jakarta.servlet.http.HttpServletRequest;
import jakarta.servlet.http.HttpServletResponse;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import java.io.IOException;


/**
 * 检查用户是否已经完成登录
 */
@WebFilter(filterName = "loginCheckFilter", urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    // 路径匹配器,支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;

        // 1.获取本次请求的URI
        String uri = request.getRequestURI();

        log.info("拦截到请求:{}", uri);

        // 定义不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login",
        };

        // 2.判断本次请求是否需要处理
        boolean check = check(urls, uri);

        // 3.如果不需要处理 则直接放行
        if (check) {
            log.info("本次请求不需要处理:{}", uri);
            filterChain.doFilter(request, response);
            return;
        }

        // 4-1.判断后台登录状态 如果已经登录 则直接放行
        Object employee = request.getSession().getAttribute("employee");
        if (employee != null) {
            log.info("用户已经登录,用户id为:{}", employee);

            Long id = (Long) employee;
            BaseContext.setCurrentId(id);

            long ThreadId = Thread.currentThread().getId();
            log.info("线程id为:{}", ThreadId);

            filterChain.doFilter(request, response);
            return;
        }
        // 4-2.判断移动端登录状态 如果已经登录 则直接放行
        Object user = request.getSession().getAttribute("user");
        if (user != null) {
            log.info("用户已经登录,用户id为:{}", user);

            Long id = (Long) user;
            BaseContext.setCurrentId(id);

            filterChain.doFilter(request, response);
            return;
        }

        log.info("用户未登录");

        // 5.如果未登录 直接返回登录结果,通过输出流向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
    }

    /**
     * 路径匹配 检查本次请求是否需要放行
     *
     * @param uri
     * @param urls
     * @return
     */
    public boolean check(String[] urls, String uri) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, uri);
            if (match) {
                return true;
            }
        }
        return false;
    }
}
